10 PRINT "DEC. OCT."
20 FOR i=0 TO 20
30 LET o$="": LET n=i
40 LET o$=STR$ FN m(n,8)+o$
50 LET n=INT (n/8)
60 IF n>0 THEN GO TO 40
70 PRINT i;TAB 3;" = ";o$
80 NEXT i
90 STOP
100 DEF FN m(a,b)=a-INT (a/b)*b